Ordinarily leave is to be freely given in the absence of prejudice or surprise, but once discovery has been completed and the case has been certified as ready for trial, an amendment will not be permitted except upon a showing of special and extraordinary circumstances. Where the application for leave is made long after the action has been certified for trial, judicial discretion in allowing an amendment should be discrete, circumspect, prudent, and cautious. Moreover, where there has been an inordinate delay in seeking leave to amend to include a new injury, a plaintiff must establish a reasonable excuse for the delay and show that the proposed amendment has merit.
Blumenthal v. 1979 Marcus Ave. Assoc., LLC, NY Slip Op 02107 (2d Dep't March 30, 2022)
